Reclosable bag, material, and method of and means for making same

ABSTRACT

A reclosable bag, and material for making the bag, and wherein in one aspect extruded resiliently flexible plastic profiled reclosable fastener strip means for reclosable bags is located across the longitudinal formation axis of the bag wall web material, and in another aspect of the invention single strip fastener strip has at one or more suitable locations therealong separations across the profiles, such as notches, to facilitate bending or folding of the strip upon itself so that the self-interlocking profiles of the portions of the strip folded upon themselves are adapted for reclosable interlocking with one another. The interlockable portions of the strip may have separable air tight sealing ribs therealong. The web and fastener material and fastener assembly is especially suitable for machines wherein the bags are formed, filled and sealed.

BACKGROUND OF THE INVENTION

This invention relates to the art of reclosable bags, the material formaking such bags, and is more particularly concerned with bags of thekind provided with extruded resiliently flexible plastic profiledreclosable separable fastener means.

The art of making reclosable bags equipped with extruded plasticprofiled reclosable separable fastener means has seen a long period ofdevelopement as reflected in numerous patent disclosures. It has beenconventional practice to extrude plastic material in tubular or stripsheet or web form with the profiled separable fastener means coextrudedalong and parallel to the longitudinal formation axis of the web, thatis, the direction in which the web is extruded. On the other hand,prefabricated separable fastener strip means have been secured toseparately formed web and with the fastener strip means extendinglongitudinally parallel to the longitudinal formation axis of the web.

By way of example, U.S. Pat. No. Re. 29,043 is referred to as disclosingcoextrusion of web and fastener means and forming the same into bagsections.

U.S. Pat. No. 3,948,705 exemplifies the technique of securing reclosableseparable fastener strips to plastic film parallel to the longitudinalformation axis of the web by fusion or heat seal methods.

Attachment of separable fastener strips parallel to the longitudinalformation axis of the web by adhesive means is exemplified in U.S. Pat.Nos. 4,372,793; 4,354,541; and 4,355,494.

U.S. Pat. No. 4,046,408 discloses separably interlockable fastenersalong the edges of the plastic sheet material having generally arrowshaped profiles, the fasteners being either integrally extruded withflat sheets or tubes of plastic film, or supplied in the form ofextruded strips attached to the web or film by heat sealing.

According to all of those prior patent disclosures, it is necessary toprovide at least a pair of spaced longitudinally extending complementaryprofile fastener strips along the longitudinal extent of the bagmaterial web or film so that when the material is folded upon itselfalong one or more folds parallel to the separable fastener strips, thefastener profiles will be aligned with one another in interlockablerelation and extend along the top or bag mouth edges of the bag sectionsinto which the material is subdivided by sealing the same at spacedintervals across the length of the material to provide closed sides forthe bag sections.

Where separate matching strips of the web or film material carrying thecomplementary profile fastener strips longitudinally along thelongitudinal extent of the material are aligned in face-to-face relationto provide bag sidewalls, the same requirements must be met as describedfor the foldable material for fabricating the same into bag sections,except that all side and bottom edges of the bag walls must also besecured together in those completed bags.

Those prior techniques do not necessarily limit the length of bags to beproduced thereby, that is, the length from the bag top end to the bottomend of the bag, unless the bags are supplied for filling by the type offilling machines commonly referred to as form, fill and seal machines,such as exemplified in U.S. Pat. No. 4,355,494.

Where the fastener strip means are located longitudinally along thelength of the bag making web material, the length of the bags that canbe produced in the form, fill and seal machines is limited to thediameter of the filling nozzle about which the film or web material isprogressively wrapped. Further, unless the fastener profiles areinterlocked before the bag forming material is wrapped about the formingextent of the filling nozzle or at least before the usual longitudinalsealing of the joined longitudinal edges or margins of the bag formingmaterial, there is a considerable problem with attaining interlockableregistration of the fastener profiles.

Furthermore, if and when used on vertical form, fill, and sealapparatus, bag material as shown in U.S. Pat. No. 4,355,494 has certainshortcomings, as the material will produce finished bags havingreclosable fastener means running in the longitudinal formationdirection of the material and, thus, in a vertical direction along thebags. Such bags may not be commercially acceptable for some products,e.g., some types of candies, potato chips, and other snack foods.

SUMMARY OF THE PRESENT INVENTION

By the present invention, the problems, disadvantages and shortcomingsinherent in prior techniques are overcome especially as related tovertical form, fill and seal arrangements for making and filling bags,but also for bag making generally.

An important object of the present invention is to provide new andimproved bags formed from film or other web material having thereonextruded reclosable plastic fastener means extending across thelongitudinal formation axis of the web material.

A further object of the invention is to provide new and improvedmaterial adapted for making of reclosable bags having complementaryprofile extruded plastic fastener strips extending across the mouth endsof the bags.

Yet another object of the invention is to provide a new and improvedreclosable fastener equipped bag material, especially for use withvertical form, fill, and seal machines so as to produce finished bagshaving reclosable fastener means running transversely with respect tothe longitudinal formation direction of the material near the top endsof the bags.

Pursuant to the principles of the present invention there is provided anew and improved reclosable bag, and wherein the bag has a body with topand bottom ends and confronting walls, and the walls formed from webmaterial having its longitudinal formation axis extending between thetop and bottom ends of the bag body, and extruded resiliently flexibleplastic profiled reclosable fastener means secured to the walls at thetop end of the bag body and extending across the longitudinal formationaxis of the web material.

There is also provided by the present invention new and improvedmaterial for making reclosable bags, comprising a web having alongitudinal formation axis and adapted for forming into a bag with theformation axis extending between a top end and a bottom end of the bag,and extruded resiliently flexible plastic profiled reclosable fastenerstrip means secured to the web across the formation axis of the web andadapted to be located across the top end of the bag into which thematerial is formed.

By this invention there is also provided material for and a bag madefrom the material, and wherein an elongated extruded resilientlyflexible plastic profiled reclosable fastener strip is foldable uponitself into interlocking relation of the fastener profiles.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present invention will bereadily apparent from the following description of certainrepresentative embodiments thereof, taken in conjunction with theaccompanying drawings, although variations and modifications may beeffected without departing from the spirit and scope of the novelconcepts embodied in the disclosure, and in which:

FIG. 1 is a perspective view of a bag embodying features of theinvention;

FIG. 2 is a longitudinal sectional view taken substantially along theline II--II in FIG. 1;

FIG. 3 is an enlarged fragmentary vertical sectional view through thetop of the bag of FIG. 1 after it has been opened and the reclosableseparable fastener snapped together;

FIG. 4 is a schematic illustration of means for applying preformedextruded plastic profiled reclosable fastener strip means to bag formingweb material;

FIG. 5 is a schematic perspective view of a vertical bag forming,filling and sealing apparatus;

FIG. 6 is a transverse sectional elevational view taken substantiallyalong the line VI--VI in FIG. 4;

FIG. 7 is a schematic sectional elevational view taken substantiallyalong the line VII--VII in FIG. 6;

FIG. 8 is a transverse sectional plan view taken substantially along theline VIII--VIII in FIG. 5;

FIG. 9 is a view similar to FIG. 8, but showing a slight modification;

FIG. 10 is another view similar to FIGS. 8 and 9, but showing stillanother slight modification;

FIG. 11 is an enlarged fragmentary perspective view of the extrudedplastic profiled closure fastener strip means as applied to the web andprovided with a V-notch to facilitate folding;

FIG. 12 is a fragmentary sectional perspective view showing the fastenerequipped web of FIG. 11 folded and the fastener interlock;

FIG. 13 is a schematic illustration of a modified means for applying thefastener strips across the length of a web;

FIG. 14 is a top plan view of a web which has been provided across itsformation axis, i.e., its length, with separable fastener strip means bythe apparatus of FIG. 13;

FIG. 15 is a fragmentary sectional detail view showing a reclosable bagtop having sealing means associated with the separable fastener; and

FIG. 16 is a similar view showing a modification of the sealing meansand fastener combination.

DETAILED DESCRIPTION

In FIGS. 1-3 is shown a reclosable bag 20 having a body with a top end21 and a bottom end 22 and confronting walls 23 and 24. The walls 23 and24 are formed from web material which may, and for some purposesdesirably does, have its longitudinal formation axis extending betweenthe top and bottom ends 21 and 22 of the bag body, as indicated by thedouble ended dashed arrow 25. Elongated, extruded resiliently flexibleplastic profiled reclosable fastener strip means 27 secured to the walls23 and 24 at the top end 21 of the bag body extends across thelongitudinal formation axis 25 of the bag body web material.

Any material which will suit the purpose for which the bag 20 isintended may be employed. Thin sheet-form packaging material such assuitable thermoplastic, and if desired gas impervious single layer orlaminated extruded film formed from polyethylene, polypropylene, and thelike, may be utilized. Such material is adapted to be formed into bagson a continuous production line wherein the material is supplied to bagproduction apparatus which may or may not be combined with bag fillingand sealing means. Generally, because extrusion can be carried out at amuch greater speed then most bag making and filling apparatus canutilize the material, the sheet film of whatever character, hereinafterto be generically referred to as web, is rolled into suitable supplyrolls since the rolling process can be effected at the same speed as theextrusion and web curing takes place, and then the supply rolls areutilized for supplying bag making web to the bag forming apparatus,which may be combined with means for filling the bags with contents.

Extruded products, and in particular extruded web, regardless of thematerial from which the web may be extruded, including plastic materialssuch as polyethylene, polypropylene, and the like, and paper which isgenerally produced by extruding a paper making fibrous slurry from anozzle generally identified as a "slice" onto a porous forming belt,have certain telltale characteristic which will identify the formationaxis of the web to those skilled in the art. Such telltales may compriseany one or more of molecular orientation, extrusion die markings, guidemeans markings or slight scratches, grain orientation, and the like, andgenerally extending along the production or machine direction length ofthe formed web and herein referred to as "the formation axis".

Bags of the kind exemplified in FIGS. 1-3, are adapted to be made bysupplying the desired web material, whether single ply or laminated, toa form, fill and seal machine 28 schematically exemplified in FIG. 5.Such machines are well known in the art and include a combination bagforming and filling nozzle cylinder 29 adapted to receive product to befilled into the formed bags from a hopper 30. Bag making web 31 carryingthe reclosable fastener or zipper means 27 extending across theformation axis of the web at suitably longitudinally spaced intervalsalong the web, is guided as by means of guide roller 32 to thecylindrical outer surface of the cylinder 29.

At the cylinder 29, a folding or wrapping arm device 33 guides and wrapsthe web 31 about the cylinder 29 with the longitudinal margins of theweb brought together into a longitudinal, laminar closure fin assembly34. Sealing of the fin assembly 34 into a closure seam is effected bymeans such as a pair of vertical sealing bars 35 which are movable froma spaced clearance relation into clamping and sealing engagement withthe closure fin assembly 34, as indicated by the solid directionalarrows 37. The bars 35 are then separable as indicated by the dashedarrows 38 to release the heat sealed seam section of fin 34 of the nowclosed bag forming tube of the web material.

Advancement of the longitudinally sealed tube by bag length incrementsis effected by means of a pair of horizontal, parallel bag end sealingbars 39 which are reciprocatingly operable, in a manner similar to thefin sealing bars 35, for clampingly engaging the bag web tube below theend of the cylindrical forming and filling nozzle member 29 forsimultaneously sealing the top end of a filled bag section 20 and thebottom end of the next succeeding bag section. Then the sealing bars 39still gripping the bag web tube, move downwardly a bag section length asindicated by the directional arrow 40 to pull and advance the entire bagmaking tube one bag increment downwardly. As this occurs, the nextsucceeding bag is filled with product dropped down the cylinder 29 fromthe hopper 30. As the sealing and pull down bars 39 reach the lower endof their sealing and pulldown stroke, severance means such as a cutoffbar 41 cuts midway across the seal 42 that has been effected by the bars39, thus releasing the previously filled bag 20 which may then behandled as desired, such as to be packed for market. Having completedits downstroke, the sealing bar and cutoff device 39, 41 returns asindicated by the dashed directional arrow 43 to its starting positionadjacent to the lower end of the cylinder 29. It will be understood, ofcourse, that operation of the vertical sealing bars 35, and thehorizontal sealing and pulldown bars 39 are operated in coordinatedcyclical relation, as is well known in the art for form, fill and sealmachines of this type.

One salient aspect of the present invention resides in having thereclosable fastener means 27 extend across the longitudinal formationaxis 25 of the web material 31, and so located that as each of the bags20 is completed, the reclosable sealing means 27 will be at one end,which subsequently may become the top end of the bag body and inside ofthe top end seal 42 of the bag completed. Through this arrangement, thebags formed in the machine 28 may be of any desired length, within thereciprocal range of the sealing bars 39. On the other hand, the maximumlength that has been attainable heretofore was limited by the diameterof the cylinder 29 so that for different bag lengths, different diameterforming cylinders had to be provided. In the prior bags the reclosablefastener extended longitudinally parallel to the longitudinal seamformed by the vertical sealing bars 35, rather than extending parallelto the horizontal sealing and pull down bars 39 as is effected by thepresent invention which attains great versatility as to the length ofbag that may be produced for any given width of bag made on a particulardiameter of forming and filling cylinder.

In one preferred arrangement, the fastener means 27 may be secured tothe web material 31 in an assembling and securing station upstreamadjacent to the form, fill and seal machine 28, as exemplified in FIGS.4, 6 and 7. Preformed extruded plastic, profiled reclosable fastenerstrip 44 may be fed from a supply roll 45 to and across and secured tothe web 31 which in operation is caused to advance toward the machine 28as indicated by the directional arrow 45 in FIGS. 4 and 7. Such advanceof the web 31 may be effected step-by-step by means of driven pinch feedrolls 47 driven as by means of a motor 48 in coordinated relation withthe step-by-step advance of the formed bag tube in the cyclicaloperation of the machine 28. Coordinated feed of the fastener strip 44to the web 31 may be effected by means of pinch type feed rolls 49driven step-by-step as by means of a motor 50 coordinated with operationof the machine 28 and the motor 48.

Upstream from the fastener guide and feed rolls 49, the fastener strip44 with its base supported on an elongated anvil or pressure bar 51 andwith interlockable profiles 52 projecting upwardly, is provided withlongitudinally spaced V-notches 53 by the operation of means such asnotching tools 54. These tools are located at suitably spaced relationto one another along the length of the fastener strip 44 depending uponthe width of the bags to be made from the web 31 after the fastenerstrip 44 has been secured to the web.

As best visualized in FIGS. 11 and 12, the profiles of the fastenerstrip 44 are preferably of generally arrow shape in cross section andthere are a plurality of the profiles, such as three, extending inspaced parallel relation along the fastener strip 44. The notches 53extending across the profiles are aligned with fold lines 55 at whatwill be the closed sides of one of the completed bags 20. The notches 53facilitate bending or creasing of the base of the fastener strip forinterlocking of the fastener profiles 52 by folding over the assemblyonto itself as indicated in FIG. 12. Further, the notches 53 facilitateinterlocking of the profiles 52 when they are brought into bag closingrelation and effect relative lateral adjustment to one another from theaxial alignment in which they were formed in the fastener strip. Suchlateral adjustment which is minor, but necessary to permit the profilesto interlock on the folded strip, is indicated by the directional arrows57 in FIG. 12. By having a plurality of the parallel fastener profiles52, interengagement of the profiles of the folded section is facilitatedsince critical lateral alignment is not necessary.

In the finished fully sealed bag the profiles 52 may remain separated asshown in FIG. 2 until the top end or mouth of the bag has been opened asshown in FIG. 3 for access to contents in the bag, and then the bag canbe closed by interengagement of the fastener profiles as shown in FIG.3. Opening of the bag may be effected either by pulling the seal 42 atthe top end of the bag open, or by severing the top end of the bag alonga line 58 between the seal 42 and the reclosable fastener 27 and thenusing the sidewall portions 59 located outwardly from the fastener 27 aspull flanges for pulling the closed fastener open when desired. Simpledigital pressure applied to the folded over portions of the strip 44 ofthe fastener 27 effects interlocking of the profiles 52.

Returning to FIGS. 4, 6 and 7, sectional lengths of the fastener strip44 which may be equal to the width of the web 31 are adapted to beguided into position across the web by means comprising a vacuum head 60carried by a reciprocatable traverse bar 61 by which the vacuum head 60is caused to extend across the width of the web 31 to bring the vacuumhead 60 into position downstream adjacent to the feed rolls 49. Theserolls are sufficiently spaced from the adjacent edge of the web 31 toprovide for a terminal portion of the fastener strip 44 to be inposition in each strip section positioning cycle to be engaged by thevacuum head 60 which is then actuated to shift back across the web 31 asindicated by directional arrow 62 to guide the fastener strip as engagedby the vacuum head 60 into position across the web, as shown in FIG. 6.As thus positioned, the cross-web section of the fastener strip 44 issecured to the web 31 by fusion bonding or adhesive bonding, as may bepreferred. For example, where the web 31 and the fastener strip 44 areof a fusion compatible material such as polyethylene, direct fusionbonding may be effected. Where the web 31 and the fastener strip 44 arenot fusion compatible, such as where the fastener strip 44 is apolyethylene extrusion and the web 31, or at least the surface of theweb to which the fastener strip is to be bonded is polypropylene, thebase surface of the fastener strip 44 may carry heat reactivatableadhesive such as a hot melt adhesive. Then, after the section of thefastener strip 44 that has been guided across the web 31 is in positionto be bonded to the web 31, a sealing head bar 63 underlying the web 31,in cooperation with a superjacent retaining and pressure bar 64, effectsfusion bonding, or reactivates the adhesive carried by the base of thefastener strip, to secure the fastener strip section permanently to theweb 31. In coordinated relation with its securement to the web 31 thesection of the fastener strip 44 is severed from the strip supply as bymeans of a cutoff device 65.

After bonding of the notched fastener strip section 44 to the web 31,and which bonding may be effected in a dwell in the advance of the web31 coordinated with operation of the form, fill and seal machine 28, thesealing bar 63 and the retaining pressure bar 64 are released, and thevacuum head 60 is released, and the web 45 may be advanced a bag lengthsection toward the machine 28. In order to avoid damage to the profiles52 of the fastener section 44 now bonded to the web 31, as that sectionpasses the feed rolls 47, the roll 47 which engages the fastener stripcarrying face of the web 31 may be covered with a relatively softfriction material sleeve 67.

Desirably, at the upstream side of the fastener strip securing means orstation, a pair of pinch type guide rolls 68 extend across and uniformlyengage the web 31 and in cooperation with the feed rolls 47 at thedownstream side of the station maintain a slight stretching tension onthe area of the web 31 between the rolls 47 and the rolls 68 tofacilitate attainment of optimum results in the fastener stripassembling and bonding steps.

Although as shown in FIGS. 1, 5 and 8, the longitudinal closure seal fin34 may be located on one wall of the bag 20, in this instance on thewall 24, and onto which the fin may be bent over during the bag endcross sealing effected by the sealing and pull down bars 39, thelongitudinal sealing may alternatively be effected along one side of thebag as shown in FIG. 9. For this purpose, the vertical sealing bars 35are located along what will become one side of the bag and thelongitudinal sealing thus effected may be permitted to remain as thatside of the bag. In such event, only one V-notch 53 need be scored orcut in each bag section of the fastener strip 44, with such notchlocated to be at the opposite side of the bag, that is directly oppositethe vertical seal fin 34.

On the other hand, if desired, the vertical closure seal for the bagmaterial may be effected by lapping the longitudinal margins of the webinto laminar relation generally in the plane of the tubular form intowhich the web is shaped about the forming and filling nozzle cylinder.To effect such a seal, a technique, substantially as exemplified in U.S.Pat. No. 3,789,888 may be employed wherein a single vertical sealing barcarried by a swing arm may be employed. For this technique, the webmargins are wrapped into overlapping relation and each succeeding bagsection has the overlapped margins sealed together with the adjacentends of the fastener strip 44 at the lapped vertical seal along one wallof the bag. Also for this arrangement the dual V-notches 53 are utilizedacross the fastener profiles.

Instead of the vacuum head and sealing bar applicator arrangement ofFIG. 4 for assembling and securing the fastener strip 44 to the web 31,a rotary fastener strip applicator 71 as exemplified in FIG. 13 may beemployed. For this purpose, the applicator 71 comprises a rotary drum 72which is adapted to be rotatably driven in step-by-step coordinationwith a form, fill and seal apparatus as exemplified in FIG. 5, where itis desired to apply fastener strips 44' to the web 31 at a locationadjacent to such a machine. On the other hand, if it is desired topreform a large endless sheet quantity of the bag making web 31 equippedwith fastener strip sections 44' secured across the longitudinal formingaxis of the web for future use, the applicator drum 72 may be rotatedcontinuously for applying the strip sections 44' to the continuouslytravelling web at bag length intervals. In any event, the drum 72 isprovided at peripherally spaced intervals such as quadrantly withaxially extending pockets 73 receptive of the desired length of fastenersection 44'. At a loading station, a loader 74 loads the proper lengthfastener strip section into one of the pockets 73, with the profiles 52extending inwardly toward the root of the channel-like pocket. Apneumatic means comprising a vacuum source may be applied to the pocket73 being loaded to assure firm retention of the fastener strip 44'therein. The loaded pocket then moves with rotation of the drum 72 to aheating station where means such as a heating roll 75 heats the exposedbase of the fastener strip. Such heating may be simply to preheat thebase for direct fusion to the web 31, or it may be for the purpose ofreactivating a reactivatable adhesive carried by the base of the strip.From the heating station, the strip is carried on by rotation of thedrum 72 for application to the web 31. For this purpose, a heatedrotatably driven roll 77 may be provided to underly the web 31 innipping relation to the drum 72 and the preheated fastener strip isbrought into position in the roll nip for bonding to the web 31. At thispoint, pneumatic expulsion pressure may be applied to the strip carryingpocket 73 to apply a firm uniform bonding pressure to the strip backedup by the roll 77. The bonded fastener strip then leaves the pocket 73,and the pocket advances toward the loading station to be reloaded withanother strip 44'.

An advantage of the rotary applicator 71 is that the fastener stripsections 44' may be of any preferred differential in length relative tothe width of the web 31. As shown in FIG. 14, for example, the fastenerstrip sections 44' may be shorter than the width of the web so as toleave a marginal area 78 along each longitudinal edge of the web betweensuch edge and the adjacent end of the fastener strip 44' in eachinstance and with the fastener strip sections 44' located at the desiredspacing 79 along the length of the web 31. At suitable intervals alongthe length of each of the fastener strips 44', notches 53' similar tothe notches 53 in FIG. 11, are formed across the profiles of thefastener strip to facilitate bending along lines 55' when the bag makingmaterial assembly is formed into bags. Since the margins 78 of thematerial are free along the entire longitudinal length of the web 31,overlapping of such margins during bag formation is facilitated forsealed seam closure, in the manner described in relation to FIG. 10.

It will be appreciated, that if instead of having the fastener stripfoldable onto themselves as has been described, for example as describedin connection with FIGS. 11 and 12, complementary fastener strips may besecured across the formation axes of separate longitudinally extendingweb sheets or panels and the sheets or panels then brought intoface-to-face relation with one another and with the complementaryfastener strips aligned for reclosable bag interengagement in the bagsmade from the material. Equipping the web with the fastener strips atrelatively high speed and to continuously running web may be effected bymeans of the applicator 71.

Where the fastener-carrying web material is fed to a bag makingapparatus immediately after securing of the fastener strips thereto, asecond rotary applicator may be provided for applying complementaryfastener strips to a second running web and the two webs carrying thecomplementary fastener strips being then joined downstream from theapplicators in the bag making process line.

Where it is desired to provide a reclosable fastener bag with bag makingmaterial such as represented in FIGS. 11 and 12, but further equippedwith means for securing a substantially air tight closure, thearrangement shown in FIG. 15 may be employed wherein the bag material isprovided adjacent to the separable fastener, or as part of the separablefastener, with a closed cell elastomer sealing rib 80 folded upon itselftogether with the associated fastener strip 44 and adapted when thefastener profiles 52 are snapped together to press sealingly togethersubstantially as shown. In one preferred form, the close cell elastomersealing rib 80 may be applied as a coextrusion onto a flange extension81 along the side of the strip 44 which will be located at the innersideof the bag.

On the other hand, an air sealing arrangement such as shown in FIG. 16may be provided wherein complementary profiled fastener strips 82 and 83may be secured to the mouth end portions of a reclosable bag 84 and withclosed cell elastomer sealing strips ribs 85 carried by the fastenerstrips 82 and 83 in a manner to press against one another in the closedfastener condition of the assembly. In this arrangement, the fastenerstrip 82 may have four profiles, and the fastener strip 83 may carrythree complementary fastener profiles, of generally arrow shape asshown, and which interhook with one another in the closed condition ofthe fastener. If preferred a rib and groove arrangement for theinterlocking fastener profiles such as exemplified in U.S. Pat. No.3,440,696 may be employed in the arrangement of FIG. 16. It may also benoted that this U.S. Pat. No. 3,440,696 discloses techniques forproviding air seal means.

It will be apparent that although placing of the extruded resilientlyflexible plastic profile reclosable fastener strips across thelongitudinal formation axis of the web greatly facilitates and improvesthe bag length capability of form, fill and seal machine techniques, andattains the important advantage of being able to utilize single stripreclosable fastener means rather than the conventional dualcomplementary fastener strip arrangements, the single strip techniquemay also be utilized for reclosable bags or other products where afoldable closure orientation of the single strip closure means may beadvantageous. For this purpose the transversely notched profilearrangement as particularly described in connection with FIGS. 11 and 12may be utilized, or the fastener strip may be applied to the web insections derived from the same continuous supply strip and properlyaligned so that when the web is folded the fastener strip sections willbe in substantially matching, and thoroughly interlockable relation.

Accordingly, it will be appreciated that the present invention providesa new dimension for utilization of extruded resiliently flexible plasticprofile reclosable fasteners. In addition, the present invention affordssubstantial economies where dual complementary fastener strips may bereplaced by the single foldable strip technique of the presentinvention.

It will be understood that variations and modifications may be effectedwithout departing from the spirit and scope of the novel concepts ofthis invention.

We claim as our invention:
 1. A reclosable bag having a body with topand bottom ends and confronting walls, and comprising:said walls formedfrom web material having a longitudinal formation axis extending betweensaid top and bottom ends of the bag body, and the material joined toitself at a joint extending between said top and bottom ends and alongone side of the body; and a continuous one-piece extruded resilientlyflexible plastic profiled reclosable fastener strip extending acrosssaid joint and secured to both of said walls at one end of the bag body;and extending lengthwise across said longitudinal formation axis of saidweb material; said reclosable fastener strip being folded upon itself atsaid joint and having integral therewith interlockable resilientlyflexible profiles which are aligned and releasably interlockable withone another in the folded strip.
 2. A reclosable bag according to claim1, wherein said web material has at least one sealed joint along laminarlongitudinal margins forming part of at least one of said walls, andsaid reclosable fastener strip having ends in alignment with one anotherat said joint.
 3. A reclosable bag according to claim 2, wherein saidjoint extends along said one wall between said top and bottom ends ofsaid bag body and said bag body has folded opposite longitudinal sides,said strip being folded on itself at both of said folded sides.
 4. Areclosable bag according to claim 2, wherein said joint extends alongone side of said bag body and the opposite side of the bag bodycomprises said fold in said web material.
 5. Material for making aplurality of reclosable bags, comprising:an elongated web having alongitudinal formation axis and adapted for forming into bags with theformation axis extending between a top end and a bottom end of each ofthe bags; an extruded continuous one-piece resiliently flexible plasticprofiled reclosable separable fastener strip means secured to saidmaterial at bag length intervals along the length of the web andextending lengthwise across the width of the web and across saidformation axis and located across one of the ends of the bags into whichsaid material is formed and to be foldably aligned on itself forproviding a reclosable bag opening.
 6. Material according to claim 5,wherein said fastener strip means has opposite ends in alignment withits longitudinal edges of said web.
 7. Material according to claim 5,wherein said fastener strip means has opposite ends located inadjacently spaced relation to opposite edges of the web, thereby leavingfree margins of the web between said ends and said longitudinal edges.8. Material according to claim 5, wherein said fastener strip means isfoldable upon itself and has interlockable resiliently flexible profileswhich are interlockable with one another when the strip means is foldedupon itself.
 9. A reclosable bag according to claim 1, wherein saidreclosable fastener strip includes relatively softer sealing meansassociated with said fastener strip along the entire length thereof andadapted for compressible sealing engagement in the closed condition ofthe fastener strip.
 10. Material according to claim 5, wherein saidfastener strip means has means for facilitating folding of the stripmeans onto itself at one or more locations along the length of thefastener strip means.
 11. Material according to claim 10, wherein saidmeans for facilitating folding comprises one or more notches formedacross said strip means.